Large ground engaging buckets are typically provided with a series of earth-cutting teeth mounted along a forward lower lip of the bucket. The teeth are the part of the apparatus which is most subject to wear and various proposals have been made to provide configurations which allow for the efficient replacement of the tooth as it is worn during use. One such example is the tooth and wear cap assembly described in U.S. Pat. No. 4,716,667 (Martin). Even with use of the wear cap assembly, the lower surface of the bucket, particularly the underside of the tooth adapters and the portions between the teeth, is frequently subjected to considerable wear forces and tend to be relatively rapidly damaged during use.
Various proposals have been made in the past to protect the lower surface of the bucket, for example, G.H. Hensley Company has sold two-piece wear parts in the form of individual adapters which are positioned by means of a shim and welded on the forward lower lip of the bucket between the excavating teeth. In U.S. Pat. No. 4,129,952 (Olson), the bottom and sides of a bucket have welded to them strips of material containing inserts of wear-resistant material and in U.S. Pat. No. 4,086,712 (McReynolds) the bucket is provided on its underside with ribs which cooperate with a paddle plate to form a box-like reinforcement.
While the above described proposals have successfully extended the working life of a bucket between repairs, there is still room for considerable improvement and a need to provide a wear assembly which is swiftly, and hence economically, replaced with minimum down time of the apparatus, but which is, nevertheless, securely held on the bucket to minimize the risk of the wear part, the excavating tooth, or its associated adapter, becoming detached from the bucket during use.
It is an object of the present invention to provide a wear assembly and the individual parts thereof for protecting the edges of a bucket of a ground engaging apparatus to improve the resistance of the bucket to wear and extend the useful working life of the bucket and its excavating teeth between services.
It is a further object to provide a wear assembly which, while providing enhanced protection does not, by reducing the effective penetrating length of the excavating teeth, detract from the efficiency of the bucket's operation.